Arrangement at a continuous casting plant

ABSTRACT

The invention relates to an arrangement at a continuous casting plant in which a bar having a liquid core and a solidified bar shell is drawn out in downward direction from a vertically arranged, water-cooled mould. It comprises a tub which is arranged below the mould to completely surround the bar shell in circumferential direction. The tub is open at its top and serves to receive liquid metal in case the bar breaks through, thus protecting the plant parts below the mould.

Unlted States Patent 1191 1111 3,860,061 Hoyer Jan. 14, 1975 [5 ARRANGEMENT AT A CONTINUOUS 3,089,209 5/1963 Phillips 164/89 x CASTING PLANT 3,324,932 6/1967 Ayers 164/89 3,354,941 11/1967 Halsteacl 164/283 s Inventor: Otto Hoyer, Linz, Austria Assignee: Vereinigte Osterreichische Eisenund Stahlwerke Alpine Montan Aktiengesellschaft, Vienna, Austria Filed: July 5, 1973 Appl. No.: 376,737

Foreign Application Priority Data Aug. 17, 1972 Austria 7095/72 U.S. Cl. 164/153, 164/283 Int. Cl. B226 19/04 Field of Search 164/83, 89, 152, 153, 283 R,

164/283 M, 283 MS References Cited UNITED STATES PATENTS 2/1959 Wieland 164/89 X Primary ExaminerFrancis S. Husar Assistant ExaminerJohn S. Brown Attorney, Agent, or FirmBrumbaugh, Graves, Donohue & Raymond [57] ABSTRACT The invention relates to an arrangement at a continuous casting plant in which a bar having a liquid core and a solidified bar shell is drawn out in downward direction from a vertically arranged, water-cooled mould. It comprises a tub which is arranged below the mould to completely surround the bar shell in circumferential direction. The tub is open at its top and serves to receive liquid metal in case the bar breaks through, thus protecting the plant parts below the mould.

1 Claim, 2 Drawing Figures PATENTED JANI 4l975 ARRANGEMENT AT A CONTINUOUS CASTING PLANT The invention relates to an arrangement at a continuous casting plant, in particular at a plant for continuously casting steel bars, in which a bar having a liquid core and a solidified bar shell is drawn out in downward direction from a vertically arranged, water-cooled mould.

When hot liquid metals are cast continuously, in particular when steel bars are cast continuously, it may happen that liquid metal breaks through the already solidified bar shell. Such out-breaks usually occur immediately below the mould in a relatively small circumferential zone of the cast bar. Though by controlling the casting speed and cooling the bar together with measuring the bar shell thickness it is possible to obtain a high operational safety in a continuous casting plant and to keep the number of out-breaks small, such a break through of metal will remain feared as the parts below the continuous casting mould, such as supporting and guiding rollers, parts of the supporting construction and the like are damaged by the steel running out and welding with these parts. Frequently it is necessary to remove completely the supporting and guiding structure adjacent to the mould and the cooling means for the bar and to replace them by new parts so that the plant will have to remain idle sometimes up to a few days.

The invention is aimed at avoiding the described disadvantages and at providing a protecting arrangement at a continuous casting plant to prevent damages in case the metal breaks through. According to the invention this task is achieved in that below the mould a tub is provided to completely surround the circumference of the bar shell, which tub is open at its top and receives liquid metal in case the bar breaks through. Advantageously the tub is designed of two parts which are horizontally displaceable towards each other and connected to a displacing means for adjusting said parts to the bar shell.

In order that the invention may be more fully understood, it shall now be explained by reference to the accompanying drawing.

FIG. 1 is a vertical sectional view of a continuous casting plant with a mould and a supporting and guiding structure for the bar to be drawn out, which plant is provided with an arrangement according to the in vention.

FIG. 2 is a horizontal sectional view along the line IIII of FIG. 1, in which the tub comprising two parts for receiving the liquid steel is shown in the position in which it is adjusted to the bar shell.

In FIG. 1 numeral 1 denotes a vertically arranged, water-cooled continuous casting mould from which a bar 2 with a liquid core 3 and a solidified bar shell 4 is drawn out in downward direction on a supporting and guiding structure comprising rollers 5 arranged on both sides of the bar 2. The first two pairs of rollers 5 which are arranged immediately below the mould oscillate with the mould 1, i.e., they are rigidly connected with the mould. The pairs of rollers 5 below said rollers are stationarily arranged at the supporting and guiding structure. Experience has shown that the danger of metal out-breaks is given in the area of the pairs of rollers oscillating with the mould 1 and at the transition to the pairs of rollers rigidly mounted at the supporting and guiding structure. percent of all out-breaks occur at the bar edges. According to the invention below this critical circumferential zone, laterally of the bar 2, two parts 6, 7 of a tub-shaped collecting vessel for liquid metal are arranged opposite each other, which are preferably made of steel sheet. Thus the flowing out metal may solidify rapidly and weld with the tub. The tub-shaped parts 6, 7 have in their bottom rectangular or U-shaped recesses 8, 9 which correspond to the cross section of the bar. Numerals 10, II denote the side walls of the tub-parts 6, 7. Each tubpart 6, 7 is displaceable by means of rollers 12 and 13, respectively, in horizontal direction towards the bar 2, and, by means of a coupling 14 and 15, respectively, releasably connected with a piston rod 16 and 17, respectively, and a piston 18 and 19, respectively, of a cylinder 20 and 21, respectively, that may be actuated hydraulically or pneumatically.

During operation the tub-parts 6, 7 are in the position shown in FIG. 2. As soon as the metal level suddenly sinks in the mould 1 which indicates a metal breakthrough the cylinders 20, 21 are actuated by hand or automatically and brought into the closing position shown in FIG. 2. Owing to the plays 22, 23 between the tub-parts 6, 7 on the one hand and between these parts and the bar shell 4 on the other hand, the cooling water running from the bar 2, is not collected in the tub 6, 7, in which case detonating gas explosions might occur. The capacity of the tub 6, 7 is adjusted to the metal volume of the bar 2 above the area at which the break-out occurred. After the liquid metal has run out, the tubparts 6, 7 are separated from the piston rods 16, 17 by releasing the couplings 14, 15; they are removed from the bar 2 by means of a flame cutter and replaced by new tub-parts. In continuous casting plants with a bending means it is possible to provide a second protection arrangement below said means at the transition to the arcuate bar guiding structure.

I claim:

1. An apparatus for use in a continuous casting plant for the continuous casting of steel bars in which a cast bar having a liquid core and a solidified bar shell is cast in a downward direction from a water cooled mould, comprising a container positioned below the mould and adapted to substantially surround the bar shell, said container being open at its top to receive liquid metal in the event that the liquid metal breaks through the bar shell and having at least two parts which are horizontally displaceable relative to each other, and means for horizontally displacing the parts of the container relative to the bar shell. 

1. An apparatus for use in a continuous casting plant for the continuous casting of steel bars in which a cast bar having a liquid core and a solidified bar shell is cast in a downward direction from a water cooled mould, comprising a container positioned below the mould and adapted to substantially surround the bar shell, said container being open at its top to receive liquid metal in the event that the liquid metal breaks through the bar shell and having at least two parts which are horizontally displaceable relative to each other, and means for horizontally displacing the parts of the container relative to the bar shell. 